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MCCB rating for LVDC circuit

MCCB rating for LVDC circuit

(OP)
I am working on a design involving a 125 VDC (nominal) circuit, and am looking to specify a 2-pole MCCB. Although the nominal rating of my DC system is 125 VDC (62.5 VDC on negative and 62.5 VDC on positive), and is ungrounded, the system floats at 134-136 VDC. The ratings on MCCB for DC tend to be specified at 125 VDC. So I'm wondering if the voltage rating of a MCCB is the maximum rating or the nominal rating. If nominal, then my 125 VDC system (ran at 135 VDC) should match the specification, right? Any advice on this would be very much appreciated.

Thanks a bunch!

RE: MCCB rating for LVDC circuit

If no response here, then you might need to contact the OEM's Application Engineering folks.


RE: MCCB rating for LVDC circuit

I can't answer your question directly but I can say that you can up-voltage your DC breakers by putting them in series. For instance using a two pole breaker and wiring the poles in series doubles the voltage gap when the ganged breaker trips.

Keith Cress
kcress - http://www.flaminsystems.com

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